Male and female electrical connector assemblies have been used for many years in a variety of applications, wherein a plug or male connector is mateable with a receptacle or female connector. A common type of plug and receptacle connector assembly employs pin and socket contacts or terminals.
A continuing problem with electrical connectors of the character described is the deterioration of the pin and socket contacts due to electrical arcing during mating and unmating thereof. It is too expensive to fabricate entire pin contacts and socket contacts of materials which withstand deterioration due to electrical arcing. Consequently, it has become common to plate the mating surfaces of the contacts with a hard, expensive material, such as an alloy of platinum nickel. Another approach has been to weld carbon discs to the tips of the pin contacts, for instance, to prevent oxidation or other deterioration due to electrical arcing. It would be much more economically feasible if the contacts were fabricated of less expensive materials, such as a brass contact plated with tin, which does give excellent electrical connection characteristics, but such contacts are prone to deteriorate when arcing occurs during mating or unmating of the contacts.
Another approach has been to reduce arcing by placing a current-limiting resistor of a suitable value in a redundant contact arrangement. For instance, in U.S. Pat. No. 4,681,549 to Peterson, dated Jul. 21, 1987, such an approach is disclosed for avoiding arcing between a connection pad of a printed circuit board and a contact of a connector. The pad is terminated before the connection edge of the printed circuit board. The connection is bypassed with a second connection comprising another contact of the connector, another pad of the printed circuit board and a series resistor. Again, as with the expensive plating approach, such a scheme of adding resistors literally can be cost prohibitive in many applications, particularly involving high density connectors.
This invention is directed to solving these problems in a very simple connector assembly wherein each of a pair of power lines is directly wired to a respective pair of mating pin and socket contacts. One pin or socket contact of each pair is configured to initially mate before the other pin or socket of each pair. The pin and socket contacts can be fabricated of relatively inexpensive material, and the first-to-mate pin and socket contact combination can be allowed to deteriorate while the integrity of the other pin and socket combination is maintained. In other words, the first-to-mate pin and socket combination of each pair comprise "sacrificial" contacts.